+Calculates the shipped qty for this orderitem (measured in the current unit)
+and returns it.
+
+Note that the shipped qty is expected not to change within the request and is
+cached in C<shipped_qty> once calculated. If C<< force => 1 >> is passed, the
+existibng cache is ignored.
+
+Given parameters will be passed to L<SL::Helper::ShippedQty>, so you can force
+the shipped/delivered distinction like this:
+
+ $_->shipped_qty(require_stock_out => 0);
+
+Note however that calculating shipped_qty on individual Orderitems is generally
+a bad idea. See L<SL::Helper::ShippedQty> for way to compute these all at once.
+
+=item C<delivered_qty>
+
+Alias for L</shipped_qty>.
+
+=back
+
+=head1 AUTHORS
+
+G. Richardson E<lt>grichardson@kivitendo-premium.deE<gt>
+
+=cut